Motion and Focus

Next topic is motion and focusing on a picture. My experience in photography is growing by the day but something I always have trouble with is blurry photos. I have some that are not focused enough where I have half of the body is perfect and the other half is blurry in motion. It’s from lighting or my camera not focusing where I really need it to. Overall I usually need to get a better position or I need to be faster with my timing.